How do you reload a lightmap?

Hi,I've been editing light maps to accommodate the change from the default FSX gps to the RXP gps in some Carenado virtual cockpits.The changes to the bmp files are relatively straight forward, but I have not found a reliable way to reload the aircraft, including thechanged light map which is located in the airplane's texture.XX file.When I reselect the Aircraft from the aircraft selection screen, it will reload, but mostly, the old light map will still show up...Only shutting down FSX and restarting will reliably give me the new light map. This really slows down editing :( Is there a way to force FSX to refresh the textures?